The Multistore model of Memory'

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The Multi-store model of Memory.

• Use the following questions to help you
  structure some notes on this model.
• Who developed the multi-store model of memory?
• Which approach in psychology is this model based
  on?
• Does this model emphasise the processes or the
  structure of memory?
• Draw the diagram on page 264. Make it clear
  (possibly by using different colours) which
  aspects relate to the structure and which relate
  to the processes involved in the model.

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Sensory memory.

• Key characteristics of the sensory memory store-
• large capacity
• very short duration no more than 2 seconds
• each sense has a separate store
• information is not really processed just
  held until brain can decide to discard it or
  attend to it (i.e. transfer it into short-term
  memory).
• Studies into sensory memory
• Sperling (1960)
• using the information on page 265 summarise BOTH
  of his studies under the headings- Aim, Method,
  Results and Conclusion

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A more sensitive measure of sensory memory.

• Averbach Coriell (1961) - carried out 2
  experiments-
• 1. Aim to investigate capacity of iconic memory.
• Method Participants shown 2 rows of 8 random
  letters
• for 50 milliseconds.
• Small mark appeared over one of the letter
  positions ps had to say which letter had
  been in this position.
• Results letter identification 75 correct
• Conclusion 12 letters can be held in iconic
  memory (i.e.
• 75 of the 16 letters shown)

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• Aim to investigate duration of sensory memory.
• Method Ps shown a letter, then, after a very
  short time interval, shown another letter.
• Results if time interval was less than 100
  milliseconds
• superimposition occurred
• e.g. F then L becomes E
• If time interval was more than 100
• milliseconds displacement occurred
• e.g. F then L becomes L
• Conclusion Iconic store lasts for approx 100
• milliseconds.
• Iconic store forgets by displacement.

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• A key component of the multi-store model of
  memory is the distinction between Short-term
  memory (STM) and Long-term memory (LTM)
• The two stores differ in terms of-
• Capacity (how much information can be held)
• Duration (how long the information is held)
• Coding (how the information is processed)

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• Results of digit span experiment
• Number of digits correct recall

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• Miller (1956) capacity of STM 7 /- 2 bits
  of information - based on digit span experiments
  and other studies.
• So STM can store between 5 and 9 pieces of
  information it has a limited number of slots
  in which information can be stored.
• But Miller did not specify the amount of
  information that can be held in each slot.

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• Try to recall the following
• 1248163264128256512
• W A N E E R
• E N D V A E
• E I A E R H
• K S Y S E T
• Z B A H I E T L E

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• We can increase the amount of information that
  can be stored in each slot by-
• Chunking grouping information so that it
  makes sense.
• Try this at home!
• write these letters on a piece of paper and see
  how many your friends and family can recall
• MSCGCSEPHDBSCAS

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• Now write them out again but this time chunk
  them so that they make sense-
• MSC GCSE PHD BSC AS
• and see how many a different set of friends can
  recall. (Think - why a different set of friends?)
• Which group remembered the most?
• Can you explain these findings in terms of
  Millers ideas about the capacity of STM?
• Write this up on a separate sheet for homework
  using the headings Aim, Method, Results and
  Conclusion

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• Try to recall the following sequences of words in
  the correct order-
• Boat foot trousers sack cup folder down nappy
  table envelope

12

• Sit down ball train house
• plane shoe light basket
• key

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• there are seven days
• Pencil tractor window
• Bottle ruler chair

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• Psychology is very
• interesting but more
• complicated than people
• think

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Duration of STM

• Aim Peterson Peterson investigated the
  duration of STM.
• Method Asked Ps to remember trigrams (groups of
  3 consonants which dont make sense e.g. KMG
  or PNS)
• To prevent rehearsal Ps were asked to count
  backwards, aloud, in 3s from a specified
  number (e.g. 361) for 3,6,9,12,15 or 18
  seconds after presentation.
• Results Even with such small amount of info,
  nearly 70 forgotten after 9 secs delay and 90
  forgotten after 18 secs (Remaining 10
  thought to be transferred to LTM

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• Conclusion STM lasts for a matter of seconds.
• N.B. Some research studies have found that
  material can be held in STM for 30 secs it
  probably depends on the type of information to be
  stored.
• Generally, STM is considered to last for
  approximately 18 30 seconds

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Coding in STM

• Use the information on page 266 and 267 to answer
  the following questions
• What are the three different ways in which
  information can be coded in our memory stores?
• How did Conrad demonstrate the STM uses a
  phonological (acoustic) code? summarise the
  study in terms of Aim, Method, Result and
  Conclusion
• Summarise both of Baddelys studies using your
  own words.
• How do STM and LTM differ in terms of the coding
  used to store the information?

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Duration of Long Term Memory

• Bahrick, Bahrick and Wittlinger (1975)
• Aim to investigate duration of LTM
• Method asked Ps aged 17 74 to write down
  names of high school class mates.
• Results recall very poor even recent graduates
  could only recall a few dozen names.
• Those out of school for more than 40 years
  could only recall on average 19 names.
• Recognition much better 90 correct
  identification of former classmates even with
  people who had left school 35 years ago!

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• Conclusion when using recall as a measure of
  memory,
• duration of LTM does not appear to be
• very good, but recognition tasks indicate
• that LTM can last for many years, possibly
• a life-time?

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Serial position curve(see activity 4 on green
handout)
Primacy effect words transferred to LTM
Recency effect words still in STM
No. of Ps recalling word
Words in middle dont get into LTM but are not
still in STM either
Position of word in the list
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Summary of multi-store model of memory

• Summarise what you have found out about this
  model in the following table
• You will need to refer to your text book and the
  handout
• Evidence Evidence Pros Cons
• for model against

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• Evidence for the model-
• 1. difference in coding between STM LTM.
• 2. serial position curve (primacy /recency
  effect)
• 3. HM poor LTM but STM okay.
• Evidence against-
• 1. KF STM (verbal) very poor but LTM
  relatively okay so info does not have to go
  through STM to get into LTM.
• 2. STM can use semantic code and uses info from
  LTM to chunk info in STM.
• Eysenck Keane can acquire info we dont
  rehearse but info presented over and over
  sometimes doesnt get stored in LTM.

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• Pros-
• 1. Stimulated a lot of research.
• 2. Relatively straight-forward.
• 3. Distinguished between structure and process
  in
• memory research.
• Cons-
• 1. Oversimplified a complex situation.
• 2. Focussed too much on structure, not enough
  on
• processes in memory.
• 3. STM and LTM are not unitary stores.
• 4. Takes no account of the nature /type of info
  
• focuses only on quantity (e.g. can remember
  football scores but not birthdays!)

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Quick quiz on Multi-store model of memory.

• 1. What are the three processes involved in
  memory?
• Registration (encoding), storage, and retrieval.
• 2. Name two ways in which memory can be measured
• Recognition, recall, memory span, paired
  associate recall.
• 3. What is meant by a) structure
• b) process in memory research?
• a) Structure way system is organised.
• b) Process activities occurring in the system
• 4. Who proposed the multi-store model of memory?
• Atkinson Shiffrin (1968)

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• 5. What approach is this model based on?
• Information processing approach mental
  operations can be understood by comparing them to
  the operations of a computer.
• 6. Draw a diagram of the model. (see pg 264 in
  textbook)
• 7. Which parts of the model relate to processes
  and which to the structure?
• Processes attention and rehearsal
• Structure 3 memory stores (sensory memory, STM
  LTM)
• 8. What is the sensory memory?
• Large(ish) capacity storage systems hold
  unprocessed info for very short period of time
• 9. How many sensory memories do we have?
• Five one for each sense modality (i.e. visual,
  auditory, touch, taste and smell)

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• 10. What is the capacity and duration of Iconic
  (visual) sensory memory?
• Capacity 12 letters. Duration less than half
  a second /100 milliseconds
• 11. Outline two key characteristics of short-term
  memory.
• Limited capacity 7 /- 2 bits of info, short
  duration (18 30 secs), coding largely acoustic,
  any distraction causes forgetting
• 12. How can the capacity of STM be increased?
• Chunking imposing meaning /grouping info so
  that it makes sense.
• 13. How is information transferred from STM to
  LTM?
• Via process of rehearsal

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• 14. Outline two differences between STM and LTM
• Coding largely acoustic for STM, largely
  semantic for LTM.
• Capacity limited for STM, unlimited for LTM
• Duration short for STM (18 30 secs), possibly
  a lifetime for LTM
• 15. Describe a study into
• a) Sensory memory
• b) STM
• c) LTM
• N.B. - for each study outline the aim, method,
  results and conclusion.
• Check in your notes, handouts, text book for
  these!